Material of construction.



, PATENTBD MAR. 20, 1906.

. W. MUESER. MATERIALS 0P CONSTRUCTION.

' QHM wMW-B APPLICATION FILED OUT. 13, 1904.

' .ifthey around the body of the bar in 0 WILLIAM MUESER, OF'VNEWY-ORKQN. Y. 3

MATERIAL OF CONSTRUCTION.

Specification of Letters Patent.

Patented larch 2D, 1906.

Application filed October 13,1904. Serial No. 228,342.

To all whom, it may concern: Be it known that 1, WILLIAM Mousse, acitizen of the United States, and a resident of New York, in the countyof New York and State of New York, have invented certain new and usefulImprovements in Materials of Construction, ofzwln'ch the following is aspecification.

My invention relates to concrete-steel construction, and its noveltyconsists in the construction and adaptation of the parts, as will bemore full hereinafter pointed out. In structures 0 this class the idealto be attained is to provide a core or bar of steel in a surroundingenvelop of concrete, each so fashioned with respect to the other thatthe strength of the unit throughout shall be uniform and so interlockedthat no separation or rupture can occur between the metal and itsplastic envelop and no sliding or slipping can take lace between theircontacting surfaces. ngineers have sought tosolve this problem byroviding steel bars with depressions and e ovations arranged in numerousforms; but so far asknown to me such ba'rs meet the requirement ofsubstantially uniform ultimate or breaking strength they have no uniformelon ation, or stretch under stress, or are of such s ape that they aredifficult to manufacture, or have sharp corners and .edges which cutinto the surrounding envelop when strained, or have some he quality,such as a tendency to slip or twist.

I have invented a form of bar to be used in combination with a concreteenvelop as a unit of construction which 'I believe possesses the idealadvantages above referred to and has none of the disadvantages stated.In, brief, it consists of a core of steel comprising a longitudinal'bodyprovided-externallywith continuous ribs wound spirally posite directionsand intersecting at regu ar intervals. The cross-section of the riboutside of the-body of the bar is tooth-she ed. The concrete beingplaced in between t ediamond-shaped de-'. pressions formed b theintersecting spiral ribs and also surrou ding the entire surface of thebar, the latter is held in place without being permitted to be twistedor rotated or pulled out under an strain which will not ru ture the bodyof t e bar itseli.

' n the drawings, Figure 1 is a-longitudinal elevation of a barembodying my invention, showing the concrete envelop in-section intwoplanes, the outline of the her being posite direction,

shown dotted where it is concealed. Fig.2 is a transverse section on theplane of the line 2 2 in Fig. 1. on the plane of the line 3 3 in Fig. 1.Fig; 4 is a similar section on the-plane of the inc 4 4 in Fig. 1. Fig.5 is a longitudinal central section through the bar and its envelop onthe plane of the line 5 5 in Fig. l, and Fig. 6 is an elevation-of thebar without its-surrounding envelop. i

In the drawings, 20 is a bar of metal which Fig. 3 is a similar section.has beenrolled or otherwise shaped into the form shown in Figs.l'andfi. It is composed in this instance of a substantially cylindricalbody 21 and is provided externally with one or more spiral ribs orprojections, as at 22 220, running around the body in one direction, andone or more ribs or ro'ections, as at 23 239, running around the 0 y inan opthe ribs intersecting those running in the opposite direction atsubstantially regular intervals, as at 24, 25, 26, 27, 28, and 29, atwhat are practically right anglbels. The ribs 22 220 and 23 230 arerefera bod of the bar. The ribs themselves may be ma e of any ap rovedform in cross-section; but the )rcferalile form jsomewhat resembles thatof t 10 teeth of ordinary cog-wheel gearing, asshown in Fig. 4. If thebar be out by several planes at right angles to its longitudinal axis,as shown in Figs. 2, 3, and 4, it will be noticed that thecross-sectional areas of the ribs at their intersections 24, 28, and 29,for insfince, as shown in Figs. 2 and 3, are about equal to theircrosssectional .areas when out se arately by a similar intersectingplane, as siown in big. 4. Wherever the two spiral ridges meet, theangle between the ridges is rounded out just enough 'to make the areasof the intersections 2S and 29, as shown in Fig. 3, equal-to areas ofthe separate ribs 22 and 23 of any cross-section, as shown in Fig. 4. Inother words, the oross sectional area of the bar, including that of thebody and ribs, is substantially constant at all points along its length.From this it follows that the bar is of substantially uniform strengththroughout. It will be understood, of course, that each bar is embeddedin a concrete envelo .30.

- T 's form'of bar has several advantages:

' Fi -t. Thes iral ribscanbemade ashighas may strength of the barwithout losing its uniform strength or any of the other adyantages thatbe desire and so as to develop the fullmade continuous and integral withthe this-bar possesses. I By developin the full strength ofthe bar Imean that it s all'be. so

firmly held in its envelopthat'itis impossible pull the bar out of thesurrounding conc'rete envelo and that if the effort is made ,the baritse must rupture, but not pull out' ltis' evident, therefore, that Ican make the ats high'enoughv to effect the result absolutely; butwhatever therelative height of n theribs to the diameter ofthe bar thecrosssectional area remains uniform, and therefore also the strength Theimportance. of-

e seen if it is remembered this advantage will that bars which haveheretofore been used .15 have been provided with corrugations orrofactionsforthe'purposeof gaining a hol on the sul 'rounding envelo butwh ch were of i e shape that the uni ormity of the area ofcrosssectfio'n was. destroyed, resulting in ac ,loss' 'offmetal of fromfive to twenty per ",cefit.: '1br, in other words, the metal ro ecsedforrengaging the envelo id not d" ,tlolth'est'rength of the bar itse f,or only of' 'the metal in the bar is reaehedthat is, if

my bar is, in tension or compression, in its '-"lon gitudin'al axis asit would be when actuintervalsbetween any two cross-sections of the barelon ate or shorten a like amount. The cau'se'oi' this uniformity of"elongation canf be ex lained as follows-;,If We consider twoclose y-adjoining. crossssections of the 4'." v bar, .welhaye ineither thecircular area of the 'jar and in addition four projections representingthe cross-section of the four ribs. 4 The only difference between thesetwo sec- 5 c tioris is to be found in the location of the fourprojections relative to the center part of the ar, two and-two'oftheeach other a certain amount. If we consider ,a' third cross-section,equally distant from the second as the 'secondis from the first, we"find the samecondition' repeatedthat is, 'two and two projections; haveagain neared each other an equalamount and as much-as wj'a's he casebetween'the first andsecondsections. So on, if consecutivecross-sections equally distant from each other are 'considered, we findthat two and two projections consecutively come closer and closertogether at perfectly uniform ratio until each two of 1 This bein no'tthecase inmy fWe kn bars do'not have this advanta e, because on 90 ofthe elastic limit of the material.

allyused in building construction-",all equal projections nearing theprojeetions meet, which point represents erases ,the crossing-points ofthe spirals, and as soon as each-two projections meet, harrinformed oneprojection of substantially doub e Width, they separate again andinconsecutive cross-, sections they go farther and farther apart at 7 0the a same ratio as they were nearing each other until the cross-sectionat the next oint Where the two spiral ribs cross is reache and It istherefore quite evident that when this bar is rolled the rolls of themill must exert exactly the same pressure in rolling a part of the barwhich lies between any two cross-sections above discussed. In otherwords, on account of the similar character of all cross-sections of thebar and on account 180 of the uniform ratio of change in location of theprojections representing the spiral ribs the metal must flow through therolls perfectly uniformly and under the same amount of pressure. Since,therefore, the character and amount of pressurejwhich are necessar toform any art of the bar are uniform, itfis c ear that the ar must haveuniform elongation. ow from experience that other forms of account oftheir form one section of the bar has to be ressed muchharder anddifferently in manufacture than many other sections, and frequentlythere are sudden changes in form of adjoining sections which prevents auniform flow of the metal through the rolls. The matter ofuniformelongation is very important in practice, as the bars naturallyare not used up to the breaking-point, but inside TOO Fifth. Anotheradvantage follows from the reasoning 'ust above made, together with thefact that t ere are two spiral continuous ribs which at all points formthe same angle with the longitudlnal center line of the bar, which isthat the ribs provide a continuous uniform hold of the same characterfor the surround-- 1ng concrete envelop along the full length of thebar, while other forms of bars provide a hold on the surroundingconcrete only at no shorter or longer interva s.

Sixth. The double spiral counteractsefi'ectively any tendency. to twistor turn under stress. I

Seventh. My bar has no sharp edgesv or n 5 corners, which under stresswould have a tendency to cut into the concrete envelop but that on thecontrary, itwill be noticed I that whiie the whole surface ofthe bar iseasily and effectively eniaged by the concrete 12:0

cutting. v

What I claim as new is* g 1. A bar adapted to'he used as a core to beembedded in concrete comprisin larly-form'ed central body provideenvelop there are no s arp corners to induce with -external projectingribs extendinga substantial part of the Ian th of the body, one of saidribs extending iagonally around thebody in one direction and another ofsaid ribs extend- 150 I a regudiagonally around the body in an oppoisitedirection and intersecting the first n I embedded in concrete comprisin'part 0 larly-formed central bodyfprovide with external rojecting ribsextending a substantial the length of the body a plurality of said ribsextending diagonally around the body in one direction and a plurality ofsaid ribs'extending diagonally around the body in an opposite directionand intersecting the first-named plurality of ribs.

- 4. A bar adapted to be usedas a core to be embedded in concretecomprisin a reguternal rojecting ribs extending a larly-formed centralbody provide with exsubstantial part 0 the len 11 of .the body, one ofsaid ribs extending iagonally around the body in one directionandanother of said ribs extending diagonally around the body inan"opposite direction and intersecting the first rib, the transversesection at the intersection of the ribs being increased to produce alongthe whole bar-a substantially uniform cross-section.

V eused asa core to be embedded n concrete comprism a regu- -part 0-body in one direction ribs extendingldiagonally-around thebody manopposite 5, Abar adapted to be-used as a core to be embedded in concretecomprising a; regularly-formed central body provide with ex:

, ternal projecting ribs extending a substantial part 0 the le h of thebody, one of said ribs extending one direction and a plurality of saidribs extendin diagonally around t e body in an oppositeirection andintersecting the first ri the transverse section at the intersection ofthe ribs being increased to produce alongthe whole bar a substantiallyuniform cross-section.

6. ,A bar adapted to be used as a core to be embedded in concrete comp aregularly-formed central body provide with external rejecting ribsextending a substantial the length of the body, a plurality of ona lyaround the a plurality of said said ribs extending dia an ection andintersecting the first-named pluralityvof ribs, the transverse sectionat the intersection of the ribs being increased to produce along thewhole bar a substantially uniform cross-section. Witness 'my hand this11th day of October, 1904, at the city of New York, 'in the county andState of New York. y WILLIAM MUESER.

Witnesses: i F HERMAN MEYER,

- ALAN MODONNELL.

agonally around the body in

